Having trouble transferring SMF's from PC to my DR-880

[Mr songwriter]

OK, I'm running Windows XP on a PC that is well in excess of the minimum spec, I've used quite a few different USB devices on this PC before (cameras, scanners, graphics pad etc) with no probs, I also followed the instructions on the USB driver CD to a T, but when I go into USB:SMF import mode (as per p135 of the manual) Windows detects the DR-880, a window pops up, I drag and drop an SMF into the Window (I've tried format 1, format 0, tiny little files) the display on the DR-880 just stays there saying:

1. copy one SMF
2.Close connection

...for hours on end. How long is it supposed to take to transfer an SMF? how large can they be and are you supposed to edit them in any way before transferring them ?(I've edited everything but the bass and drum tracks out)

I'm sure the cables good because I used it with my scanner a day or so before and I've definitely got the USB mode set to 'Storage'

Could anyone who's actually managed to transfer SMF's to the DR-880 give me some suggestions about where I might be going wrong/what I should try. Please.

[Mr songwriter]

Never mind, I found out what the problem was, I wasn't right-clicking on the device in the taskbar and selecting 'Safely remove hardware' which it appears you have to do after every file you transfer, yes, I know RTFM etc.